Citaro Fuel Cell Buses Provide Shuttle Service at Davos

28 Jan 2013

Two Mercedes‑Benz Citaro FuelCELL Hybrid buses with fuel cell technology provided both shuttle and regular services from 23 to 27 January 2013 at the prestigious "World Economic Forum" in Davos.

PostAuto is the first bus company in Switzerland to use fuel cell technology in public transport. Since the end of 2011, five Mercedes‑Benz Citaro FuelCELL Hybrid Postbuses have been employed on PostAuto regular service routes in and around Brugg (Aargau canton). PostAuto is carrying out a long-term test of fuel cell drive systems. The fuel cell Postbuses use only environmentally-friendly and sustainably produced hydrogen as a fuel. PostAuto estimates that 2000 tonnes of CO2 will be saved during the five-year test phase.

When compared to the fuel cell buses which were tested from 2003 within the framework of the CUTE and HyFLEET:CUTE projects, the new Citaro FuelCELL Hybrid boasts fundamental innovations: hybridisation with energy recovery and storage in lithium-ion batteries, high-performance electric motors with 120 kW continuous power in the wheel hubs, electrified PTO units and further developed fuel cells. These will achieve an increased durability of at least five years or 12,000 operating hours. The fuel cell stacks of the new Citaro FuelCELL Hybrid are identical to those of the Mercedes‑Benz B‑Class F‑CELL with a fuel cell drive system. Both stacks are located on the vehicle's roof as was the case with earlier fuel cell buses. The lithium-ion batteries which, for example, store recovered power during braking are a new addition to the roof. The power provided by the energy reservoir means that the new Citaro FuelCELL Hybrid can travel several kilometres using only battery-electric power.

In principle, the concept of the new FuelCELL bus correlates with the Mercedes‑Benz BlueTec Hybrid buses. A diesel generator still provides these with the necessary electric energy. In contrast, on the new FuelCELL buses, it is the fuel cells which generate electrical current for the drive motors which boast zero-emissions.

Thanks to the improved fuel cell components and the hybridisation with lithium-ion batteries, the new Citaro FuelCELL Hybrid saves 50% hydrogen in comparison to the previous generation. As a result the number of tanks has been reduced from the nine necessary for the previously tested fuel cell buses to seven and a total of 35 kg of hydrogen. The range of the fuel cell buses is greater than 300kilometres. Thanks to these diverse technical improvements, purely electric omnibuses with fuel cells for energy generation are a definite step closer to being ready for series production.